In the knitting and weaving industry, there is a widespread dependence of overall quality in most textile processing on the precision and uniformity of tension of the individual yarn ends when weaving or knitting a fabric material. Once yarn tension control is lost or allowed to vary at any point of the process, whether winding, beaming, texturizing, knitting or other fabric formations, the quality degeneration is difficult or impossible to compensate for. Streaking, barre, off yield, excessive knitting defects, denier variation, are familiar problems that frequently have their origin in incorrect or uncontrolled tension of the individual yarn ends.
Probably the most common type of tension device in current use is the post and disc type tensioner wherein the yarn is routed around circular posts to generate friction and build tension. The advantage of this type of tensioner is its simplicity and low cost, but it has a significant disadvantage in that the tension developed by the wrapping depends on how much tension is in the yarn as it approaches the wrapped post. Since the tension in the yarn leaving such a tensioner is equal to the tension from the yarn source times a constant K determined by the wrap angle or number of posts, and the tension of the yarn going into the post and disc unit is usually uncontrolled, multiplying the supply or feed yarn tension by some factor simply makes the tension larger but still uncontrolled.
There remains a need for a durable, anti-static tension device for use with cones of high twisted yarn in the manufacture of knitted or weaved fabric materials, such that as yarn is fed to a knitting or weaving machine at a positive rate of speed, the tension device will prevent slippage of the feeding yarn; and as the yarn approaches the tension device, the anti-static disc will prevent the yarn from being pulled towards the outer disc surface and will also prevent the doubling-up of the yarn as it feeds into the anti-static disc and tension assembly.